Snap fastener stud and method of forming same



Nov. 16, 1965 R. R. AMESBURY 3,217,584

SNAP FASTENER STUD AND METHOD OF FORMING SAME Filed Dec. 11, 1962 Fig.1.2 Fig 3 9 M /2 f Q s I nveniiow'i Baker? R. Jimesbury,

United States Patent f 3,217,584 SNAP FASTENER STUD AND METHOD OFFORMING SAME Robert R. Arnesbury, Wellesley, Mass, assignor to United-Carr Incorporated, a corporation of Delaware Filed Dec. 11, 1962, Ser.No. 243,904 1 Claim. (CI. 8580) This invention relates to improvementsin metal snap fastener stud members and the method of forming the same.

An object of the invention is to provide a simple, inexpensive,one-piece, flexible snap fastener stud having a flange, a yieldableshank extending from the flange; and the shank having a head, a neck anda shoulder, the entire length of the fastener being divided by a slotmeans so that the stud may be stamped from a thin sheet of metal, andformed around an anvil to provide a hollow snap fastener stud.

Another object of the invention is to form a snap fastener stud by asimple blanking, forming, and bending method to produce a stud notadapted to be formed by any known metal drawing method.

In the drawings:

FIG. 1 is an enlarged view, partly in section, showing one installationof the improved snap fastener stud member;

FIG. 2 is a section taken on the line 2-2 of FIG. 1;

FIG. 3 is a top plan view of the snap fastener member per se;

FIG. 4 is a side elevational view of the fastener shown in FIG. 3;

FIG. 5 is a bottom plan view of the fastener shown in FIG. 4; and

FIG. 6 is a plan view of a strip of metal showing the blankingoperations prior to the blank being cut from the strip and bent around aforming anvil.

Heretofore, one-piece metal snap fastener stud members, of the generalshape illustrated, have been formed by a series of so-called drawingoperations and then slotting and head bumping operations in a suitablesocalled eyelet machine or press. The resulting studs have had manyuses. However, it has been impossible to manufacture that type of studof substantial length and very small diameter by such known methods. Ithas been found that there is a use for relatively long shank studs withvery small diameters for use in attaching electronic parts to a printedcircuit board where a small hole /8 of an inch or less in diameter isneeded. Furthermore, it has been found that small diameter long shankstuds of different degrees of flexibility would prove very useful.

A desired stud, meeting the requirements for various applications, isillustrated by the drawings and will be described hereafter both as tostud construction and method of manufacture.

A particularly useful snap fastener stud is shown by FIGURES 3, 4, and5. In this construction the stud has a base flange 1 and a hollow shank2 divided longitudinally throughout its length, as clearly shown in FIG.4. The shank has a head 3, a shoulder 4 and a neck 5, all as best shownin FIG. 4. The head is completely divided longitudinally by slots 6,herein shown as three in number, but any other suitable number may beused. One of the slots 6 is extended by a portion 7 through theremainder of the shank 2 and flange 1 (FIG. 4) so that together theyform the complete longitudinal division of the stud. Adjacent the slotextension 7 there is provided, at opposite sides, abutment portions 88,the use for which will be described hereinafter.

It should be noted that the base flange 1 is divided into fourindependently yieldable angled portions 9, Any other suitable number ofportions 9 may be used 3,217,584 Patented Nov. 16, 1965 but it has beenfound that relatively narrow angled portions 9 will flex readily withouttaking a set when maintained under flexed tension.

The blanking method of forming the improved snap fastener studsdescribed above is shown in FIG. 6 and two stages of the blanking andforming operation are shown. From a suitable strip of metal 10 theblanking tools provide the four portions that will make up the angledportions 9 of the flange 1 and the other three portions will make up theportions of the head 3. This form of the stud is shown in themid-section of FIG. 6. At the right of that section is shown anotherfastener blank which has been shaped by suitable tools to provide theproper relation of the portions 9 of the flange 1 by bending theportions 9 at right angles to the blank. The proper forms for the head3, shoulder 4 and neck 5 are accomplished by shaping and curving thethree portions which go to form the shank 2. After the last formingoperation is completed the blank is cut from the strip along the dottedline 11 as shown in FIG. 6 and then the formed blank is bent around asuitable shaped anvil not shown. Now that the improved snap fastenerdevice and the operations of blanking have been described in connectionwith FIG. 6 it is believed that it will be understood by anyone skilledin the art that the improved stud may be formed in any suitable machineadapted to operate with progressive blanking and forming tools withoutany drawing operations. Therefore it is unnecessary to go into detailfurther with respect to the type of equipment, formation of the blankingtools or the folding tools in this application.

One type of installation with which the improved snap fastener studs maybe used is roughly illustrated by FIGS. 1 and 2. In this case the deviceis shown in connection with electrically attaching a part 12 to aprinted circuit board 13 carrying printed circuit portions 14. Since theprinted circuit portions 14 are usually very narrow it is necessary toform relatively small holes through the printed circuit board, and it isalso desirable that the fastener be held tightly in position and thatthe parts of the installation be clamped together strongly to providefor good electrical connection between the parts. Therefore, therelatively long shank small diameter stud is shown as having its head 3passing through an aperture 15 in the part 12 and then through anaperture 16 in the printed circuit board 13 so that the shoulder 4 makesa tight contact against a printed circuit portion 14. The neck 5 ispreferably longer than the thickness of the entire installation but thedistance between the shoulder 4 and the lower ends of the angledportions 9 of the flange 1 is less than the total thickness of the partsto be assembled. When the stud is snapped into position the angledportions 9 will be flattened to some extent and together with theshoulder 4 place a tension on the parts, thereby causing a goodelectrical contact.

Another important feature of the invention is the provision of theabutment portions 8-8 adjacent the slot 7 which, when the stud is usedin a small enough hole, will be brought into contact and thereby causethe three portions of the head, neck and shoulder of the shank to becompressed more tightly, during the snapping together operation and thefinal holding assembly, than would be the case if the shoulders 8-8 werenot provided. It will also be understood, by anyone skilled in the art,that the tension of the fastener may be varied by changing the lengthsof the abutments 88. Therefore, by slight changes in the blanking toolsdifferently operating snap fastener studs may be provided. Furthermore,by interchangeability of tools the length of the shank may be varied byslight changes in the tools.

It will now be understood by anyone skilled in the art that varioussizes, diameterwise, and lengths of shanks,

3 plus relative location of the shoulder 4, plus the lengths of theabutments 88 and the slots 6 may be provided by mere interchangeabilityof tools whereas such variations in previously known studs was onlypossible heretofore by completely separate sets of tools for use indrawing, slitting and shaping. It will also now be appreciated that verysmall diameter studs may be produced according to the present invention,whereas similar small diameter studs, particularly having relativelylong shanks, were impossible to produce.

While there has been illustrated and described a particular snapfastener stud construction, One useful installation of the snap fastenerconstruction and a more or less diagrammatic blanking disclosure, bywhich the improved fastener stud may be made, it should be understoodthat the inventions are best defined by the following claim.

I claim:

A snap fastener stud formed from a single piece of material foldedlongitudinally to provide a split base flange and a generally tubularshank with spaced opposed edges throughout its length to provideflexibility for contraction and expansion of the base flange and shank,said shank having an enlarged head portion providing a shoulder, a neckportion and a plurality of slots extending into said shank from saidhead end and terminating in said References Cited by the Examiner UNITEDSTATES PATENTS 1,344,596 6/1920 Schaefer 855 1,978,087 10/1934 Johnson855 2,560,530 7/1951 Burdick 855 FOREIGN PATENTS 647,180 12/1950 GreatBritain.

EDWARD C. ALLEN, Primary Examiner.

